Humans are the only mammals who are NOT equipped with a protective biological mechanism that breaks down methanol into harmless formic acid. This is why animal testing of aspartame does not fully apply to humans

Recent research also suggests that sucralose (Splenda) may have neurotoxic effects

By Dr. Mercola

Most public health agencies and nutritionists in the United States still recommend no- or low-calorie artificial sweeteners as an acceptable, and even preferred, alternative to sugar. This flawed advice can have very serious repercussions for those who follow it.

Artificial sweeteners of all kinds have been found to wreak havoc with your health in a number of different ways. Aspartame, which is perhaps the worst of the bunch, has a long list of studies indicating its harmful effects, ranging from brain damage to pre-term delivery.

Aspartame is also the number one source of side effect complaints to the US Food and Drug Administration (FDA), with over 10,000 complaints filed and over 91 documented symptoms related to its consumption.

Most recently, studies are also starting to confirm lingering suspicions that artificial sweeteners like aspartame may play a role in the development of Alzheimer's disease, a serious form of dementia that is now thought to kill over half a million Americans each year.

The key mechanism of harm appears to be methanol toxicity—a much-ignored problem associated with aspartame in particular.

In a previous interview, toxicology expert Dr. Woodrow Monte (author of the book While Science Sleeps: A Sweetener Kills1), explained the links between aspartame and methanol toxicity and the formation of formaldehyde. In light of the latest research, this interview is more relevant than ever, which is why I included it again.

Methanol Toxicity Leads to Persistent Alzheimer's Symptoms

A recently published two-part paper2,3 highlights what Dr. Monte has been saying for many years now—that methanol acts differently in animals and humans. In this case, the researchers also discovered changes in effect between mice and rhesus monkeys.

Methanol-fed mice presented with partial "Alzheimer's disease-like symptoms," while rhesus monkeys fed a 3% methanol solution developed persistent pathological changes related to the development of Alzheimer's. According to the authors:

"A recently established link between formaldehyde, a methanol metabolite, and Alzheimer's disease (AD) pathology has provided a new impetus to investigate the chronic effects of methanol exposure.

This paper expands this investigation to the non-human primate, rhesus macaque... [M]ethanol feeding led to persistent memory decline in the monkeys that lasted 6 months beyond the feeding regimen...

Most notably, the presence of amyloid plaque formations in the monkeys highlighted a marked difference in animal systems used in AD investigations, suggesting that the innate defenses in mice against methanol toxicity may have limited previous investigations into AD pathology.

Nonetheless, these findings support a growing body of evidence that links methanol and its metabolite formaldehyde to AD pathology." [Emphasis mine]

The Link Between Aspartame and Methanol Toxicity

The artificial sweetener industry (and makers of artificially sweetened products) has fervently claimed that aspartame is harmless, and that there's "no biological explanation" for the health problems reported by so many after consuming aspartame.

But as explained by Dr. Monte, there is indeed a biological and scientific explanation for aspartame's pathway of harm, and as the latest research suggests, it's related to the effects of methanol and formaldehyde, both of which are extremely toxic.

Aspartame is primarily made up of aspartic acid and phenylalanine—the latter of which has been synthetically modified to carry a methyl group. This is what provides the majority of the sweetness. That phenylalanine methyl bond, called a methyl ester, is very weak, allowing the methyl group on the phenylalanine to easily break off and form methanol.

You may have heard the claim that aspartame is harmless because methanol is also found in fruits and vegetables. However, in these whole foods the methanol is firmly bonded to pectin, which allows it to be safely passed through your digestive tract. This is not the case for the methanol created by aspartame. There, it's not bonded to anything that can help eliminate it from your body. That's problem number one...

Problem number two relates to the fact that humans are the only mammals who are NOT equipped with a protective biological mechanism that breaks down methanol into harmless formic acid. This is why animal testing of aspartame does not fully apply to humans.

According to Dr. Monte, the fact that methyl alcohol is metabolized differently in humans compared to other animals has been known since 1940. And according to the featured paper, rhesus monkeys do not appear to have the same defenses against methanol toxicity as mice do. This basically negates much of the animal research that has been used to "prove" aspartame's safety.

Methanol Acts as a Trojan Horse in Your Body

As explained by Dr. Monte, in humans, methanol ends up acting as a Trojan horse, allowing toxic formaldehyde to wreak havoc in some of your most sensitive areas, such as your brain. Here's how it works: both animals and humans have small structures called peroxisomes in each cell. There are a couple of hundred in every cell of your body, which are designed to detoxify a variety of chemicals. Peroxisome contains catalase, which help detoxify methanol.

Your cells also contain alcohol dehydrogenase (ADH), which converts methanol to formaldehyde. Other chemicals in the peroxisome in turn convert the formaldehyde to formic acid, which is harmless—but this last step occurs only in animals. Human peroxisomes cannot convert the toxic formaldehyde into harmless formic acid.

Certain locations in your body, particularly in the lining of your blood vessels, and in your brain, are loaded with ADH that converts methanol to formaldehyde. But since there's no catalase present, the formaldehyde does not get converted into harmless formic acid. As a result, the formaldehyde is free to do enormous amounts of damage in your tissues.

Symptoms of methanol poisoning include: headaches, ear buzzing, dizziness, nausea, gastrointestinal disturbances, weakness, vertigo, chills, memory lapses, numbness, and shooting pains in the extremities, behavioral disturbances, and neuritis. The most well known problems from methanol poisoning are vision problems including misty vision, progressive contraction of visual fields, blurring of vision, obscuration of vision, retinal damage, and blindness. Formaldehyde, in turn, is a known carcinogen that causes retinal damage, interferes with DNA replication, and may cause birth defects.

Processed Foods Are Also High in Methanol

As I've discussed in previous articles, processed foods should be avoided as a proactive Alzheimer's prevention strategy. In his book, Grain Brain, neurologist Dr. Perlmutter reveals how the toxic activity of sugar and carbohydrates in your diet promote Alzheimer's disease. But we can also add methanol to the list of reasons for avoiding processed foods. Not only do many processed foods contain artificial sweeteners, but when fruits and vegetables are canned, for example, the methanol becomes liberated from the pectin.

At room temperature, it only takes one month for 10 percent of the methanol to be released. After about six months, virtually all of the methanol is liberated. Dr. Monte is convinced that methanol and the subsequent conversion to formaldehyde from certain processed foods (see listing below), as well as all foods containing aspartame, are a major culprit in a variety of diseases, especially multiple sclerosis (MS).

Again, methanol can slip through your blood brain barrier, and your brain is one of the areas where you find alcohol dehydrogenase, which converts methyl alcohol to formaldehyde. This causes the destruction of myelin basic protein, which is one of the triggers for MS. Demyelination also plays a role in the development of Alzheimer's and several other brain-related diseases. According to Dr. Monte:

"We know that methyl alcohol is known to be a demyelinating agent... [T]he symptoms associated with the demyelination... are identical between multiple sclerosis, and methanol poisoning, and people who consume aspartame."

He believes many diseases can be prevented if we start avoiding methanol from all sources, and he even offers a methanol-free diet on his website.4 Items to avoid include:

Fruit and vegetable products and their juices in bottles, cans, or pouches

Chewing gum, as most chewing gum in the USA contains aspartame

Jellies, jams, and marmalades not made fresh and kept refrigerated

Slivovitz and other fruit schnapps

Black currant and tomato juice products, fresh or processed

Overly ripe or near rotting fruits or vegetables

The Neurotoxic Properties of Splenda

Another popular artificial sweetener is sucralose, sold under the brand name Splenda. Sucralose is a synthetic chemical created in a five-step patented process, in which three chlorine molecules are added to one sucrose (sugar) molecule. Some will argue that natural foods also contain chloride, which is true. However, in natural foods, the chloride is connected with ionic bonds that easily dissociate when ingested. In Splenda, they're in a covalent bond that does not dissociate.

And, since your body has no enzymes to break down this covalently bound chloride, harm can ensue... The reason why your body has no enzymes for this task is because, in nature, there are NO covalent chloride bonds to organic compounds—they only exist in synthetic, man-made form. Aside from Splenda, other examples of synthetic covalently bound chloride compounds include DDT, PCBs, and Agent Orange.

Previous research indicates that about 15 percent of sucralose is absorbed into your digestive system, and ultimately stored in your body fat. A 2008 animal study5 found that Splenda reduced the amount of beneficial intestinal bacteria by 50 percent, increased the intestinal pH level, and affected a glycoprotein that can have crucial health effects, particularly if you're on certain medications.

More recent research6 detailing Splenda's oxidative effects, suggests the sweetener may have neurotoxic properties, which doesn't surprise me in the least. The researchers, who assessed the effects of sucralose on water fleas, concluded that: "exposure to sucralose may induce neurological and oxidative mechanisms with potentially important consequences for animal behavior and physiology." As reported by GreenMedInfo.com:7

"Like so many novel patented chemicals released onto the market without adequate pre-approval safety studies, we do not know if this preliminary toxicological research will be applicable to human exposures. In fact, there are only 318 study citationson this chemical in existence since it first began to be researched in the 70's. This most recent study is the first in existence to look at its effect on the enzyme acetylcholinesterase, which is found in all animals.

This information deficit is all the more remarkable when you consider there are over 7,000 published studies in existence on either turmeric or its primary polyphenol curcumin, which is still not readily administered by the conventional medical establishment mostly due to 'safety concerns,' despite what the voluminous positive data on its relevance to over 600 health conditions indicates."

FDA Approval Means Little When It Comes to Ascertaining Safety

As previously noted by Dr. Janet Hull,8 many tend to excuse the negative health effects of aspartame simply because it has received the stamp of approval by the FDA. But as discussed in her article, "Abusing the FDA Approval Process,"9 the FDA requires that the industry do its own research, and actually places the burden of proof on the company making the product. Rarely is the industry research reviewed by independent researchers. Should you still be confused on this issue, thinking that the buck somehow stops at the FDA, FDA spokesman Theresa Eisenman recently clarified who is ultimately responsible for making sure a food product is safe, stating that:10"Manufacturers are responsible for ensuring that their food products are safe and lawful..."

But what company would really make a serious effort to find problems with the very products they want to capitalize on? Despite this illogical premise, the FDA trusts corporations to be honest in their research and evaluations. How likely do you think it is that this "honor system" will actually ensure that each product released to market is safe?

When it comes to artificial sweeteners, aspartame in particular, there's no doubt in my mind that the system has protected industry profits at consumers' expense. And we've not seen the last of it. Despite mounting evidence showing that artificial sweeteners as a group have adverse health effects, the FDA has just approved yet another artificial sweetener called Advantame,11,12,13 concocted from a combination of aspartame and vanillin, an artificial vanilla flavor.

Being 20,000 times sweeter than refined sugar, Advantame is the sweetest artificial sweetener so far. To put this into perspective, aspartame, sucralose, and saccharine range from 200 to 700 times sweeter than sugar. Also, as reported by the LA Times:14

"Like aspartame, advantame contains phenylalanine, which is metabolized with difficulty by people with a rare genetic disorder, phenylketonuria. But because of its intense sweetness, advantame would be used at much lower volumes than is asparatame. As a result, the FDA has declared that it can be safely consumed by those with phenylketonuria."

Having a Hard Time Giving Up Artificial Sweeteners?

When you consume artificial sweeteners, your brain actually craves more calories because your body receives no satisfaction on a cellular level by the sugar imposter. This can contribute to not only overeating and weight gain, but also an addiction to artificial sweeteners. To break free, I recommend addressing any emotional component of your food cravings using a tool such as the Emotional Freedom Technique (EFT). A version of EFT specifically geared toward combating sugar cravings is called Turbo Tapping. The video below with EFT practitioner Julie Schiffman also demonstrates how to use EFT to fight food cravings of all kinds.

If you still have cravings after trying EFT or Turbo Tapping, you may need to make some changes to your diet. My free nutrition plan can help you do this in a step-by-step fashion. As for safer sweetener options, you could use stevia or Luo Han, both of which are safe natural sweeteners. That said, if you struggle with high blood pressure, high cholesterol, diabetes or extra weight, then you have insulin sensitivity issues and would likely benefit from avoiding ALL sweeteners.

Last but not least, if you experience side effects from aspartame or any other artificial sweetener, please report it to the FDA (if you live in the United States) without delay. It's easy to make a report — just go to the FDA Consumer Complaint Coordinator page, find the phone number for your state, and make a call reporting your reaction.